Textile product



yMay 7, 1940.

-D. FlNLAYsoN ETAI. K 2,199.428

TEXTILE PRODUCT Filed Aug. 20, 1937 Patented May 7, 1940 UNITED STATESTEXTILE PRODUCT Donald Finlayson and `l'ames Frederick Levers, Spondon,near Derby, England, assignors to Celanese Corporation of America, acorporation of Delaware Application August 20, 1937, Serial No. 160,066In Great Britain September 29, 1936 22 Claims.

This invention relatesto improvements in textile products and is moreparticularly concerned with new composite yarns and with fabrics orother materials made of or containing such yarns.

It is well known that wool yarns are considerably more voluminous incharacter than cotton yarns and this is probably due at least in part tothe fact that the fibres of cotton are considerably straighter than woolfibres and are comparatively short in length so that it is necessary toinsert a substantial amount of twist in a cotton yarn in order to obtaina coherent product, which reduces the voluminosity of such yarn.Moreover, wool has a much greater elasticity both in the dry and wetstate than has cotton.

For some purposes the voluminous andv elastic character of wool yarnspresents considerable advantages and a great deal of research has beendirected in recent years to the production of articial yarns which havethe voluminous character of wool yarns. The results obtained, however,have not been entirely satisfactory since the products do not comparefavourably with wool as regards their properties of voluminosity,elasticity and non-crushability. For this reason many socalledartificial wools hitherto marketed have contained substantialproportions of natural wool, e. g. 50-75% of natural wool.

It has now been discovered that products which have a very high degreeof voluminosity and elasticity may be produced by associating a bundle,cr yarn having at most only a low degree of twist, of crinkled filamentsof cellulose acetate (as heremafter referred to) with a yarn having arelatively high twist, i. e. a twist of the order of that necessary toimpart to the yarn the capacity of shrinking on treatment with hotaqueous liquors. The yarn of high twist is hereinafter. referred to asthe basic yarn of the composite product. It is important, in order toobtain the best results, that the yarn or bundle of crinkled laments ofcellulose acetate (hereinafter referred to as the voluminous component)should be present in preponderating proportions in the final product.Preferably, therefore, the basic yarn should constitute as low aproportion as 30%, 20% or even less of the total denier of the compositeproduct.

Crinkled filaments of cellulose acetate are obtained by subjectingbundles or yarns of cellulose acetate filaments, especially such ascomprise filaments of flat or nearly flat cross-section, to the actionof hot or boiling water, or preferably hot or boiling dilute soapsolutions. The flat type Vof filament is preferably produced by spinninga cellulose acetate solution in a normal way into an evaporativeatmosphere but using a concentration of cellulose acetate in the acetoneor other volatile solvent'lower than is customarily used to produce thebulbous type of lament. However, the flat type of filament may also beproduced by spinning the cellulose acetate solution into an evaporativeatmosphere which contains a high concentration of solvent for celluloseacetate near the spinning jets. Alternatively, or in addition, thespinning solution may contain paradichlorbenzene or other plasticisngagent as described in British Patent No. 459,781. Other things beingequal, a higher degree of crinkling, and therefore of voluminosity, isobtained with the higher lament deniers. The crinkling of the celluloseacetate filaments may be effected, for example, by treating suchfilaments, e. g. in the form of hanks of yarn, with hot aqueous liquors,and especially with hot dilute soap solutions, without tension so y asto develop the crinkle in the filaments. The crinkle developed by theabove processes is irregular in character.

Again, crinkle is imparted to cellulose acetate filaments by processessuch as those described in U. S. Patents Nos. 2,089,198 and 2,089,199and British Patent No. 464,981. These processes consist, broadly, inimparting a twist to the yarns, setting the twist in the yarns, e. g. bythe action of steam, and thereafter untwisting the yarns. Preferably theoperation is effected with a false twisting device. Such processesimpart a spiral crinkle to the filaments. If desired the crinkling ofthe filaments may be accomplished by a combination of the two methodsdescribed above, e. g. a yarn or bundle of fiat filaments of celluloseacetate may be subjected to one of the processes of U. S. Patents Nos.2,089,198 and 2,089,199. and British Patent No. 464,981 and, eitherbefore or after such treatment, subjected to the action of hot aqueousliquors.

The iilaments in the voluminous component may be continuous, as isnormal in the production of cellulose acetate artificial silk, or may bediscontinuous, provided that the length ofthe staple in the product isnot so short as to necessitate a relatively high degree of twist toproduce a coherent product. A staple length of -8'or 10 inches or moremay be used but preferably the staple is as long as possible, e. g. ofthe order of 18 inches.

The basic yarn may be of cellulose acetate or any other suitablematerial for example of any other organic derivative of cellulose, or itmay be of the regenerated cellulose type, e. g. viscose or cuprammoniumsilk or yarn obtained by complete saponiiication of cellulose acetatematerials, or it may be a partially saponifled cellulose acetatematerial or may consist of a yarn of normal cellulose acetate which hasbeen subjected to a process of acetylation as described, for example, inBritish Patents Nos. 448,816 and 448,917. Or, again,l the basic yarn maybe of cotton, wool or natural silk. For reasons which are set out belowit is especially advantageous to `employ as the basic yarn a product ofhigh tenacity, for example a cellulose acetate yarn which has beenstretched considerably so as to impart to it a high tenacity, or theproduct obtained by partial or complete saponication of such yarn. Byemploying a yarn of considerable strength as the basic yarn it ispossible to associate with it relatively large quantities of thevoluminous component, and thus increase the total voluminosity of theproduct, whilst conserving the necessary strength for the productconsidered as a whole. It is frequently advantageous, especially in thecase of cellulose acetate materials and in the case when very hightwists are being inserted, to insert the twist in the basic yarn of thecomposite product while the yarn is under the influence of steam or hotwater as described in U. S. Patents Nos. 2,088,628, 2,088,587 and2,089,191.

The doubling twist used to associate the voluminous component with thebasic yarn should not be so high as to reduce substantially thevoluminosity. As a result of the doubling operation the basic yarneither receives additional twist or has some twist removed therefromdepending on the relative directions of the twist in the basic yarn andof the doubling twist. For

this reason the twist in the basic yarn before' thedoubling operationshould be either in excess of, or short of, that desired in the ultimateproduct. It is usually preferable to insert the doubling twist in thesame direction as the original twist in the basic yarn so that at nostage has the basic yarn a twist higher than that inv the desiredproduct. By this means the strength of the basic yarn is conserved. Forexample when an ultimate twist of 55 turns per inch in the basic yarn ofthe composite product is desired, it is better to insert a twist of 50turns per inch and then increase this to 55 by a doubling twist of 5turns per inch in the same direction than to start with an originaltwist of 60 turns per inch and to decrease this to 55 by a doublingtwist of 5 turns per inch in the revers-e direction.

Preferably the initial twist in the basic yarn and the doubling twistare so chosen that the basic yarn in the composite product is readilycapable of being shrunk by treatment with hot aqueous liquors.

As stated above it is of the greatest importance in order to obtain thebest results that the voluminous component should be present in thecomposite products of the present invention in preponderatingproportion. The high proportion of voluminous component relative tobasic yarn may b e achieved, for example, by associating a voluminouscomponent of relatively high denier with a basic yarn of relatively lowdenier, the voluminoips component and the basic yarn being fed at thesame speed to the doubling device. Or alternatively, and this seems tobe preferable from the point of view ofthe voluminosity of the product,the voluminous component may be fed at a higher speed than the basicyarn to the doubling device, for example at a speed 5, 10, 50 or even100% or more faster than that of the basic yarn. In this way thevoluminous component appears in the composite product as if it were moreor less spiralled round the basic yarn, with the result that the lattermay be more or less embedded in the composite product. As an example ofthe relative proportions of voluminous component to basic yarn of afinal total denier of 150-200 in the composite product, the basic yarnmay have a denier of the order of 30-50. With such low proportions ofbasic yarn it is advantageous, as indicated above, that the basic `yarnshould vbe of relatively high tenacity.

In accordance with this invention a single basic yarn may be doubledwith a single voluminous component but numerous other combinations fallwithin the scope of the invention. Thus two or more voluminouscomponents may be doubled with a single basic yarn, or-two or morecomposite yarns, each containing one or more voluminous componentsdoubled with a basic yarn, may be doubled together so as to make aproduct of greater total denier. Again, a voluminous component doubledwith a basic yarn may be further doubled with an additional voluminouscomponent, or composite yarns containing one or more voluminouscomponents doubled with a basic yarn may be doubled with each other andsimultaneously with an additional basic yarn or other desired component.In each doubling operation the speed of feeding the different yarns tothe doubling device may be controlled in the manner already described soas to yield a product of high voluminosity.

Preferably the composite products are subjected to a scour so as toshrink the basic yarn before associating the composite yarn in a fabric.By this means in the weaving or knitting of the composite yarns intofabric not only does the presence ofthe basic yarn prevent undueextension of the voluminous component and thereby conserve thevoluminuous and elastic character of the composite yarn in the finalproduct but, in additional, the curl developed in the basic yarn as theresult of the shrinking treatment helps to prevent slipping of thevoluminous component along the basic yarn. However, the rough characterof the basic yarn may be suiiicient to prevent such slipping and theshrinking operation may be applied to the materials, if desired, afterfabric formation.

As indicated above, the initial twist in the basic yarn and the doublingtwist are preferably so chosen that the basic yarn in the compositeproduct is readily capable of being shrunk by Atreatment with hotaqueous liquors. This is a characteristic of high twist crpe yarn andthe shrinkage in question may, therefore, be referred to as a crpeshrinkage". The basic yarn, after it has been shrunk by treatment withhot aqueous liquors, is therefore referred to in the claims as acrpe-shrunk yarn.

Examples of composite yarns according to the invention will now bedescribed with reference to Figs. 1-5 of the accompanying diagrammaticdrawing.

In the drawing:

A is a 170 denier yarn of crinkled cellulose acetate filamentssubstantially free from twist.

B is a denier viscose crpe yarn containing 40 turns per inch S twist.

C is a 75 denier viscose crpe yarn containing 33 turns per inch S twist.

D is an denier cellulose acetate crpe yarn containing turns per inch Stwist prepared by a process in which the last part of the twist has beeninserted while the thread is under the inuence of steam. (See U. S.Patents Nos. 2,088,628, 2,088,587 and 2,089,191.)

E is a 34 denier natural silk crpe yarn containing 74 turns per inch Stwist.

F is a 75 denier viscose crpe yarn containing 40 turns per inch S twist.

Referring to Fig. 1, one end of the yarn A is doubled with one end ofthe yarn B by means of 5 turns per inch S twist. If desired thisconstruction can be modied by feeding the yarn A to the doubling devicefaster, e. g. 5% or 10% 75 faster, than the yarn B, and in this way thevoluminosity of the product may be enhanced.

In Fig. 2, two ends of the yarn A are doubled with one end of the yarnC, the yarns A being fed to the doubling device 5% faster than the yarnC, i. e. each 100 units of length of the yarn C is doubled with 105units of length of each of the yarns A. The doubling is effected by 12turns per inch S twist.

The construction illustrated in Fig. 3 is similar to that shown in Fig.2 except that one end of the yarn D is employed instead of the yarn C.

Fig. 4 illustrates a construction in which one end of the yarn E isdoubled with one end of the yarn A by means of 21 turns per inch Stwist. the yarn A being fed to the doubling device 50% faster than theyarn E, i. e. so that 100 units of length of the yarn A are doubled with150 units of length of the yarn E, and two composite yarns thus producedare doubled together by means of a 12 turns per inch Z" twist.

Referring to Fig. 5, two ends of the yarn F are doubled with one end ofthe yarn A by means of a 34 turns per inch S twist, the yarn A being fedto the doubling device at three times the speed of the yarns F, i. e. sothat 100 units of length of each of the yarns F is doubled with 300units of length of the yarn A, and two composite yarns thus produced aredoubled together by means of a 12 turns per inch Z twist. The yarnproduced in this way closely resembles a chenille yarn.

Having described our invention what we desire to secure by LettersPatent is:

1. A composite yarn resembling a wool yarn, which comprises a yarn ofcrinkled cellulose acetate filaments which in the composite yarn has atmost only a low degree of twist, doubled with a high twist yarn which inthe composite yarn has a degree of twist such that it possesses theability to shrink on treatment with hot aqueous liquors, the yarn ofcrinkled cellulose acetate filaments being present in substantiallygreater proportion than the said high twist yarn.

2. A composite yarn resembling a wool yarn, which comprises a yarn ofcrinkled cellulose acetate laments which in the composite yarn has atmost only a low degree of twist, doubled with a high twist yarn which inthe composite yarn has a degree of twist such that it possesses theability to shrink on treatment with hot aqueous liquors, the yarn ofcrinkled cellulose acetate laments being of substantially greater denierthan the said high twist yarn.

3. A composite yarn resembling a wool yarn which comprises a length of ahigh twist yarn .doubled with a greater length of a yarn of crinkledcellulose acetate laments, the said yarn of crinkled cellulose acetateiilaments having in the composite yarn at most only a low degree oftwist, and the said high twist yarn having in thev composite yarn adegree of twist such that it possesses the ability to shrink ontreatment with hot aqueous liquors, the yarn of crinkled celluloseacetate filaments being in substantially greater proportion than thesaid high twist yarn.

4. A composite yarn resembling a wool yarn, which comprises a length'ofa high twist yarn doubled with a greater length of a yarn of crinkledcellulose acetate filaments, the said yarn of crinkled cellulose acetatelaments having in the composite yarn at most only a low degree of twist,the said high twist yarn having in the composite yarn a degree of ,twistsuch that it possesses the ability to shrink on treatment with hotaqueous liquors, and the said high twist yarn constitutlng at most 30%of the total denier of the composite yarn.

5. A composite yarn resembling a wool yarn, which comprises a high twistyarn doubled with a yarn of crinkled cellulose acetate iilaments, thesaid yarn of crinkled cellulose acetate filaments having in thecomposite yarn at most only a low degree of twist, and the said hightwist yarn having in the composite yarn a degree of twist such that itpossesses the ability to shrink on treatment with hot aqueous liquors,the yarn of crinkled cellulose acetate filaments being in substantiallygreater proportion than the said high twist yarn.

6. A composite yarn resembling a wool yarn, which comprises a yarn ofcrinkled cellulose acetate laments doubled with a highly twisted yarn ofhigh tensile strength, the said yarn of crinkled cellulose acetateillaments having in the composite yarn at most only a low degree oftwist and the said high twist yarn having in the composite yarn a degreeof twist such that it possesses the ability to shrink on treatment withhot aqueous liquors, the yarn of crinkled cellulose acetate filamentsbeing in substantially greater proportion than the said high twist yarn.

7. A composite yarn resembling a wool yarn, which comprises a yarn ofcrinkled cellulose acetate filaments doubled with a highly twisted yarnof high tensile strength, the said yarn of crinkled cellulose acetatelaments having in the composite yarn at most only a low degree of twist,the said high twist yarn having in the composite yarn a degree of twistsuch that it possesses the ability to shrink on treatment with hot'aqueous liquors, and the said high twist yarn constituting at most 30%of the total denier of the composite yarn.

8. A composite yarn resembling a wool yarn, which comprises a yarn ofcellulose acetate filaments which have been crinkled by treatment with ahot aqueous liquor, doubled with a high twist yarn which in thecomposite yarn has a de gree of twist such that it possesses the abilityto shrink on treatment with hot aqueous liquors, the yarn of crinkled,cellulose acetate laments being present in substantially greaterproportion than the said high twist yarn and having, in the compositeproduct, at most only a low degree of twist.

9. A composite yarn resembling a wool yarn, which comprises a yarn ofcellulose acetate iilaments which have been crinklled by twisting theyarn, setting the twist therein and thereafter 'removing at least partof the twist, doubled with a high twist yarn which in the composite yarnhas a degree of twist such that it posssesses the ability to shrink ontreatment with hot aqueous liquors,

the yarn of crinkled cellulose acetate filaments being present insubstantially greater proportion than the said high twist yarn andhaving, in the composite product, at most only a low degree of twist.

10. A composite yarn resembling a wool yarn, which comprises a yarn ofcrinkledy cellulose acetate filaments which in the composite yarn has atmost only a low degree of twist, doubled with a crpe-shrunk high twistyarn, the yarn of crinkled cellulose acetate filaments being insubstantially greater proportion than the said high twist yarn.

l1. A composite yarn resembling a wool yarn, which comprises a yarn ofcrinkled cellulose acetate laments which in the composite yarn has atmost only a low degree of twist doubled with a crpe-shrunk high twistyarn, the yarn of crinkled cellulose acetate filaments being ofsubstantially greater denier than the said high twist yarn.

12. A composite yarn resembling a wool yarn, which comprises a length ofa crpe-shrunk high twist yarn doubled with a greater length of a yarn ofcrinkled cellulose acetate filaments which in the composite yarn has atmost only a low degree of twist, the yarn of crinkled cellulose acetatelaments being in substantially greater proportion than the said hightwist yarn.

13. A composite yarn resembling a wool yarn, which comprises a yarn ofcrinkled cellulose acetate filaments which in the composite yarn has atmost only a low degree of twist doubled with a crpe-shrunk high twistyarn, the said high twist yarn constituting at most 30% of the totaldenier of the composite yarn.

14. Process for the production of composite yarns resembling wool yarns,which comprises associating together at least two yarns, one of which isa yarn of crinkled cellulose acetate filaments and one of which is ahigh twist yarn, the said yarn of crinkled cellulose acetate filamentsbeing present in the final product in substantially greater proportionthan the said high twist yarn and having in the final product at mostonly a low degree of twist, and the said high twist yarn having in thefinal product a degree of twist such that it possesses the ability toshrink on treatment with hot aqueous liquors.

15. Process for the production of composite yarns resembling wool yarns,which comprises doubling together at least two yarns, one of which is ayarn of crinkled cellulose acetate filaments and one of which is a hightwist yarn, the said yarn of crinkled cellulose acetate filaments beingofl substantially greater denier than the said high twist yarn andhaving in the final product at most only a low degree of twist, and thesaid high twist yarn having in the final product a degree of twist suchthat it possesses the ability to shrink on treatment with hot aqueousliquors.

16. Process for the production of composite yarns resembling wool yarns,which comprises feeding to a doubling device a yarn of crinkledcellulose acetate laments and a high twist yarn,

the former yarn being fed to the doubling devicev at a speed greaterthan the latter yarn and the doubling twist being such that the saidyarn of crinkled filaments in the final product has at most only a lowdegree of twist and the said high twist yarn has a degree of twist suchthat it possesses the ability to shrink on treatment with hot aqueousliquors.

17. Process for the production of composite yarns resembling wool yarns,which comprises feeding to a doubling device a yarn of crinkledcellulose acetate filaments and a high twist yarn, the former yarn beingfed to the doubling device at a speed greater than the latter yarn andthe doubling twist being in the same direction as the twist in the hightwist yarn and being such that the said yarn of crinkled laments in thefinal product has at most only a low degree of twist and the said hightwist yarn` has a degree of twist such that it possesses the ability toshrink on treatment with hot aqueous liquors.

18. Process for the production of composite yarns resembling wool yarns,which comprises doubling together at least two yarns, one of which is ayarn of crinkled cellulose acetate filaments and one of which is a hightwist yarn, in -such proportions that the said high twist yarnconstitutes at most 30% of the total denier of the product, and so thatthe said yarn of crinkled filaments possesses in the final product atmost only a low degree of twist and the said high twist yarn possessesin the final product a degree of twist such that it possesses theability to shrink on treatment with hot aqueous liquors.

19. Process for the production of composite yarns resembling wool yarns,which comprises doubling together at least two yarns, one of which is ayarn of crinkled cellulose acetate filaments and one of which is ahighly twisted yarn of high tensile strength, in such proportions thatthe said high twist yarn constitutes at most 30% of the total denier ofthe product, and so that the said yarn of crinkled filaments possessesin the final product at most only a low degree of twist and the saidhigh twist yarn possesses in the final product a degree of twist suchthat it possesses the ability to shrink on treatment with `hot aqueousliquors.

the final product a degree of twist such that it possesses the abilityto shrink on treatment with hot aqueous liquors, and thereaftersubjecting the composite product to the action ofl hot aqueous liquorsso as to effect shrinkage of such high twist yarn.

21. Process for the production of composite yarns resembling wool yarns,which comprises doubling together at least two yarns, one of which is ayarn of flat cellulose acetate filaments which have been crinkled bytreatment with a hot aqueous medium and one of which is a high twistyarn, the said yarn of crinkled cellulose acetate filaments beingpresent in substantially greater proportion than the said high twistyarn, and the .doubling twist being such that the said yarn of crinkledfilaments possesses in the final product at most only a low degree of.twist and the said high twist yarn possesses in the final product adegree of twist such that it possesses the ability to shrink ontreatment with hot aqueous liquors.

22. Process for theproduction of composite yarns resembling wool yarns,which comprises doubling together at least two yarns, one of which is ayarn of cellulose acetate filaments which have been crinkled by twistingthe said yarn, setting the twist, and removing at least part of thetwist, and one of which is a high twist yarn, the said yarn of crinkledcellulose acetate filaments being present in substantially greaterproportion than the said high twist yarn, and the- DONALD FINLAYSON.JAMES FREDERICK LEVERS.

